Wikipedia
Arthrophyllum is a defunct genus of flowering plants in the family Araliaceae. It was recognized by most authors until 2010, when all of its 30 species were "sunk" into ''Polyscias'' subgenus Arthrophyllum.
Arthrophyllum is mostly a genus of shrubs and small to medium trees, but it contains a few large trees, and in New Caledonia, a few lianas, as well. They are noted for their large and apparently leafy inflorescences, up to across. The fruit is 1- seeded and the ovary is unilocular. The genus is indigenous to Indomalesia and islands of the southwestern Pacific.
The most widespread and variable of the species is Polyscias jackiana (formerly Arthrophyllum jackianum). Until 2003, it was usually treated as conspecific with Polyscias diversifolia. The New Guinea species Polyscias macranthum can occasionally become quite large and is locally used for lumber.
The four species from New Caledonia were once placed in a separate genus, Eremopanax, distinguished by seeds containing smooth endosperm, versus ruminate endosperm for Arthrophyllum. It was later determined that this character does not clearly distinguish the two genera, and they were united under Arthrophyllum by William Raymond Philipson in 1978, bringing the total number of species up to about 30. For Arthrophyllum in New Caledonia, the taxonomic history is complex, because the species are not clearly distinct, and their circumscription has varied greatly from one author to another.
According to Index Nominum Genericorum, no type species was ever designated for Arthrophyllum. When the former genus Arthrophyllum became part of Polyscias subgenus Arthrophyllum in 2010, Polyscias diversifolia was designated as the type for the subgenus. Polyscias subgenus Arthrophyllum consists of all of the 30 species from the former genus Arthrophyllum, all of the four species from the former genus Kissodendron, and four species already placed in Polyscias.